Ground electrode for spark plug



FIG. 1 is a top perspective view of a ground electrode for spark plug, showing my new design;

FIG. 2 is a side elevation view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is another top perspective view thereof.

The broken line showing of the environment is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a ground electrode for a spark plug, as shown and described. 